JP2761088B2 - Apparatus and method for detection of filaments - Google Patents

Description

Description: FIELD OF THE INVENTION The present invention relates to a method and an apparatus for detecting activated elongated threads on or in a sheet.

[Problems to be solved by conventional technology and invention]

The use of filaments for security purposes, for example magnetic or luminescent filaments, is well known in the field of documents to be secured, for example banknotes.
Conventional magnetic security filament detection systems include a magnetization station that activates the filament. Banknotes are transferred through the magnetizing station and then through the reader. The function of the magnetization station is to change the magnetic material to a known magnetic state. The magnetic field generated from the magnetic material is detected by a magnetic read head in a detector.

Some of the magnetic filaments are coded, i.e., the magnetic filaments are not made of a continuous, relatively uniform strip of material, but are composed of several zones, some of which are Including magnetic materials, some include magnetic materials with different properties or none at all. The pattern of magnetic material on the filament can be used to encode banknotes, whereby currency units, issue dates, etc. can be determined.

One current design for reading codes is to use a permanent magnet to magnetize the material as it is transported long edge first, and to use a conventional magnetic read head assembly to present the presence of a thread. And patterns. (GB-A-2098768
reference). The head assembly is wide enough so that the device covers the transport path where the filaments should appear if all of the supply tolerances and the tolerances for the location of the filaments are given. It must be something. Such an arrangement is not possible for banknotes transferred with the short edge first. A single large head may not be able to identify the magnetic pattern, thus requiring one or more rows of heads.

The dimensions of each head cannot be made larger than the individual magnetized areas, and the rows of heads must span banknotes (or at least a large part of them). A typical magnetized region is about 2 mm high and a row of heads can typically be about 100 mm high, so a row of heads typically has 50 to 200 read heads. May need to be included. Since each of the read heads requires a channel for electronic processing, the overall system is quite large and expensive.

The technique disclosed in U.S. Pat. It indicates that there is difficulty. The purpose of the prior art is to read a grid printed with magnetic ink behind the head of the president on the surface of a U.S. banknote. These grids can be viewed as two simple "codes" printed respectively parallel and perpendicular to the long edge of the banknote.

If a bank note can be considered to be transferred with a short edge preceding it, there is no problem reading a line perpendicular to the long edge with a read head having a sensing gap parallel to the line. However, as the patent recognizes, lines parallel to the long edge cannot be detected by the read head, regardless of whether the gap is parallel to the long or short edge.

The technique of U.S. Pat.
5 degrees) to move past the read head. This technique allows the two "codes" to be read simultaneously.

It is difficult to design a high-speed banknote transfer device that can transfer banknotes in this manner. All practical devices move the banknote in a direction substantially parallel to one edge (long or short edge) of the banknote. Banknotes for secure athletic walkways or restricted areas of transfer
The problem of maintaining a 45-degree angle is severe.

[Means for solving the problem]

According to a first aspect of the present invention, there is provided a detection device for detecting an activated elongated filament on or in a sheet, the device comprising: an elongated detector; A movement means for effecting relative movement between the sheet and the sheet, wherein the detector extends at an acute angle to the filament in use, whereby the filament is distinct from the detector. There is provided a device for detecting a fibrous body, wherein the device is adapted to be sequentially provided to portions.

According to a second aspect of the present invention, there is provided a method for the detection of activated elongated filaments on or in a sheet, the method comprising the steps of: Generating relative motion, wherein the relative motion is such that the detector extends at an acute angle to the filament in use, whereby the filament is sequentially provided to different portions of the detector. A method for detecting a fibrous body, the method comprising:

In the present invention, by arranging the detecting means at an acute angle with respect to the filament, a situation in which a large number of individual sensors are required can be avoided.

In one example, one detector is provided, and in another example, a set of detection means comprising a plurality of detectors is provided, each detector being used with respect to the filament in use. Extending at an acute angle, each detector is arranged such that each detector detects a different portion of the filament. In such other examples, the need to provide a relatively large detector is avoided. A single detection means is difficult and expensive to manufacture and requires a relatively large portion of the transfer path.

Several sets of processing electronics, typically between two and ten sets of processing electronics, are required depending on the number of heads, but for the large row of detection means in question above. The number can be significantly reduced from a very large number of required sets, and the required transfer path length is significantly smaller than in systems utilizing a single detector. For example, if the detectors are arranged at a 45 degree angle to the direction of travel of the banknotes, four detectors with a width of 36 mm cover a banknote with a height or width of 100 mm. And only a transfer of about 25 mm is required. Thus, there is the problem of further and thus significant savings in system complexity and price. The preferred number of the detection means is 2 to 10, and the most preferred number is 4 to 8.

The present invention can be used with various types of filaments, but is particularly applicable for the detection of magnetic filaments. Preferably, the detection device further includes an activation unit for activating the filament.

This is an illumination system that emits light in the case of a luminous thread, and can be a magnetic station if the thread is a magnetic thread.

In a preferred embodiment, the means for generating the relative movement comprises a conveyor system for moving the sheet past each detecting head.

The invention is particularly suitable for detecting filaments in individual sheets, but can also be used to detect filaments on continuous sheets (webs). Further, the detection device can be used to detect a thread that can reach the head from various directions.

〔Example〕

Three specific examples of the thread detection device and the thread detection method according to the present invention will be described below with reference to the drawings.

FIG. 1A shows a conventional banknote 1 having a security thread 2 extending parallel to the short side. The security thread 2 includes a plurality of magnetic material portions 3, some of which can be seen in the enlarged view of FIG. 1B. Typically, the filament 2
Has a width between 0.5 mm and 1.0 mm, and each part 3 has a width between 1.0 mm and 2.0 mm.
It has a length between mm. Thus, in the section of the filament 2 shown in FIG. 1B, a single portion 3A and a double portion 3B are shown. These parts 3A and 3B are composed of parts 4 which do not contain magnetic material or which contain materials having different magnetic properties.
Are separated by

The selection of the parts 3A, 3B etc. is used to code the security thread 2.

FIG. 2 schematically shows an example of a detecting device for detecting the security thread 2. The apparatus comprises a conventional magnetizing station 5 below which a conventional belt conveyor system (not shown).
Are supplied in direction 6 with shorter edges first.
A long magnetic read head 7 is arranged downstream of the magnetizing device 5. The head 7 is inclined at an angle of about 45 degrees with respect to the direction of the filament. Although other angles are possible, this is the preferred angle. If the angle is sharper,
The head will occupy a longer portion of the transfer, and less acute sharpness can degrade the identification of signals, eg, from individual bars of code. It is immaterial whether the tip of the head is inclined or away from the direction of transfer.

As can be seen from FIG. 2, when the banknote is transported under the head 7, the thread portion passes sequentially through the corresponding lower portion of the head and the thread is effectively moved along the head. Scanned. The head 7 generates an electrical signal representative of the strength of the incident total magnetic field, which is effectively equal to the magnetic field by the appropriate part of the filament, which electrical signal is in conventional manner
It is output to the remote processing electronics 20 as a single channel.

FIG. 5 is a diagram showing a more detailed configuration of the apparatus shown in FIG. In this example, the banknote 1 is transferred between input belts 30 of a transfer system stretched around rollers 31. The banknote 1 is discharged from between the rollers 31 and is supplied to a nip formed between the magnetic read head 7 and a spring-loaded guide 32 fixed to a fixing member 33. Guide body 32 loaded with spring is banknote 1
Is maintained in contact with the magnetic head 7, whereby the banknotes are pushed by the movement of the belt 30 so that the leading edge of the banknotes is between the rollers 34 which run each output belt of the transfer system. It is brought into contact with the magnetic head 7 until it is accepted.

In some cases, the devices of FIGS. 2 and 5 can be difficult to manufacture and require expensive large heads. Further, a transfer path occupying a relatively large portion is formed by the head.

FIG. 3 shows a variant in which the head 7 is replaced by a group of three short heads 8 to 10 which are arranged substantially parallel to one another along a line diagonal to the transfer direction of the banknote 1. I have. Each head means 8 to 10 respectively scans an individual part of the thread 2 and produces an output signal which is a function of the part of the thread being scanned. In this case,
Three sets of processing electronics 21-23 are required, one for each head, each processing electronics includes an amplifier, a peak detector, and an analog storage device. 23 are connected to an arithmetic processing means 24 for generating an arithmetic result signal for identifying the filamentous material, but the price and complexity of this device are as high as 50 to 200 detections as described above. Not very expensive compared to the price and complexity of the system including the means.

FIG. 4A shows another specific example in which three long detection heads 11 to 13 are used. The heads 11 to 13 are arranged at a predetermined angle with respect to the banknote transfer direction indicated by the arrow 14, and the heads are mutually offset in the banknote transfer direction and in a direction perpendicular thereto.

The output signals from the heads 11 to 13 are 15 in FIG.
Through 17 individually. As can be seen in FIG. 4B, the output signals from the heads 11 to 13 are displaced in time with respect to each other, and the three signals are sent to an arithmetic processing circuit 18 to function as one signal. Where the signal is integrated into an output waveform 19 representing the entire filament.
Generate.

The method of calculating the signal from each head is already known to those skilled in the art. For example, in a multiple head system such as that shown in FIG. 3, each of the processing electronics 21 to 23 operates on the signals from each head, then digitizes those signals, and during the transmission thereof. The signal is delayed according to the appropriate head position. The digitized and delayed signal is then provided to a processor 24, which adds the delayed signals to generate a "complete" tracking record of the filament (the security filament). ) And further process all signals (in the case of barcodes) to generate a stream of pulses representing the bar pattern. The technique used to determine the code can depend on the design of the code.

[Brief description of the drawings]

1A is a diagram showing an example of a typical banknote having a thread, FIG. 1B is a partially enlarged view of the thread for security, and FIG. 2 is an example of a thread detector according to the present invention. FIG. 3 is a schematic view showing a second example of the thread detection device according to the present invention. FIG. 4A is a schematic diagram showing a third example of the thread detection device according to the present invention. FIG. B is a diagram showing an output signal in the device of FIG. 4A, and FIG. 5 is a diagram showing details of the device in FIG. [Description of Signs] 1... Banknotes 2... Filaments 3... Activated part 4... Non-activated part or part 3 having different characteristics from activated part 5. Apparatus, 7,8,9,10,11,12,13... Detecting means, 20,21,22,23...

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int.Cl. ⁶ , DB name) G06K 7/00 G06K 17/00

Claims (8)

(57) [Claims] 1. A detecting device for detecting an activated elongated filament on or in a sheet, the device comprising a detector between the elongated detector and the detecting means and the sheet. Motion means for effecting a mechanical movement, wherein the detector extends at an acute angle to the filament in use, whereby the filament is sequentially provided to different parts of the detector. An apparatus for detecting a fibrous body, the apparatus comprising: 2. A system comprising a set of detectors, said detectors being arranged side by side, each detector extending at an acute angle to the filament in use, so that each detector is 2. The device according to claim 1, wherein different parts of the filament are detected in each case. 3. The device according to claim 2, comprising three, four or eight detectors. 4. The apparatus according to claim 1, wherein each detector is adapted to detect a magnetic property of the filament. 5. The apparatus according to claim 1, further comprising an activating means for activating the detected characteristic of the filament. 6. Apparatus according to claim 1, wherein the means for generating relative movement comprises a conveyor. 7. Each of the detectors is substantially 45 degrees with respect to the direction of the filament.
Apparatus according to any one of the preceding claims, wherein the apparatus extends in a moderate manner. 8. A method for the detection of activated elongated filaments on or in a sheet, the method comprising generating a relative movement between the sheet and the elongated detector. Wherein the mode of relative movement is such that the detector extends at an acute angle to the filament in use, such that the filament is sequentially provided to different portions of the detector. A method for detecting a fibrous body.